[Tim isn't looking at Jacobi, just leaning on the couch staring towards the kitchen, one hand curled loosely near his mouth. It's just the slight pinch around his eyes, the tension in his jaw that betrays what a lie the casual air is.]

We got separated during Prentiss's attack. I went into the tunnels, she made it into Artefact Storage.

[He swallows, and it does nothing to alleviate his tension.]

A Stranger monster was trapped there, in a table that got brought in, and it... got her. Replaced her.